Falls greatly impact the morbidity and mortality of older adults with an estimated 20% to 35% experiencing a fall each year. Although much research has been conducted on other risk factors, there is a paucity of data on the role of footwear. The proposed research will attempt to determine the degree to which footwear affects the risk of falling in older adults. The investigators hypothesize that type and biomechanics of footwear are related to falling; specifically, increased fall risk will relate to friction and shoe structure/deformability. Prospective surveillance of falls with a nested case-control study is proposed among a random sample of elderly enrollees at Group Health Cooperative in Seattle, Washington. The study will be conducted in conjunction with a cohort study of older adults currently underway that includes an extensive cognitive and neurologic assessment at baseline. Identified during a 2-year surveillance period using a calendar/postcard/phone system, older adults who experience an unintentional fall to the ground with or without an injury (approximately 400) will be compared to age and gender matched nonfallers for differences in physical and biomechanical characteristics of footwear. Interviews and biomechanical tests on footwear, conducted at the participant's residence within two weeks of the fall, will include questions on shoe type and wear, physical activity, fall history, environmental factors, health behaviors, and current health status and medications. The biomechanics component of the on-site visit will include measurements of coefficient of friction, heel lateral stability, sole flexibility, midsole hardness, and contact area. Data collected prior to the fall will include demographics, chronic medical conditions, neurologic measures including gait, and medications. Data analysis will employ conditional logistic regression to evaluate the degree to which footwear type and the biomechanic characteristics are associated with an increased risk of falling. Potentially confounding variables such as gait, floor surface, and individual risk factors for falls, will be evaluated and controlled for when appropriate in the analysis. The investigators point out that the study utilizes an innovative multidisciplinary approach and efficiently employs an already assembled cohort to assess footwear as a risk factor for falling. They state the findings could be useful to the development and testing of health promotion efforts to prevent falls among older adults. Changing footwear could provide a relatively inexpensive way to reduce falls.